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Senate Judiciary Committee Chairman Chuck Grassley accused the top Democrat on the House Intelligence Committee, Adam Schiff, of making a "tired and baseless" claim that Grassley was trying to undermine special counsel Robert Mueller's Russia investigation.

In an interview with CBS' "Face the Nation," Schiff, D-Calif., accused Grassley, R-Iowa, of being "part of the same effort along with [House Intelligence Committee chairman Devin Nunes] to try to put the FBI and Bob Mueller's investigation on trial."

Last week, Grassley and Sen. Lindsey Graham, R-S.C., released a criminal referral they had sent to the Justice Department earlier this year asking for an investigation into Christopher Steele, the former British spy who compiled the so-called "Trump-Russia dossier."

Grassley and Graham said they found evidence that either Steele lied to the FBI, or classified documents supporting government surveillance of former Trump campaign adviser Carter Page contained false statements.

Late Sunday, Grassley spokesman Taylor Foy fired back at Schiff, saying in a statement that the Steele referral "says not one word critical of Mueller."

"If Schiff (or anyone else) is going to claim that it is Grassley’s intent to undermine the Mueller probe, they should back it up with actual evidence or retract it and apologize for questioning the motives of their colleagues without any basis whatsoever," Foy said. "Otherwise, they’re only exposing their own biases."

In a memo released earlier this month, Nunes and other House Intelligence Committee Republicans accused the FBI and Justice Department of not telling the Foreign Intelligence Surveillance Court enough about Steele's anti-Trump sentiments or that his work was funded in part by Hillary Clinton's presidential campaign and the Democratic National Committee.

The Democrats on the committee, led by Schiff, have claimed that the memo "cherry-picked" details. They noted federal law enforcement officials had informed the court about the political origins of Steele's work, some of his information was corroborated by the FBI and other evidence was used to get the warrant.

President Trump blocked the release of a Democratic rebuttal to the GOP memo Friday, citing national security concerns. The president asserted the Democratic memo was a trap meant to "blame the White House for lack of transparency" and urged the Democrats to "re-do and send back in proper form!"

Fox News' Catherine Herridge and The Associated Press contributed to this report.